The present invention relates to an apparatus for and a method of pre-exposing camera film with images.
Cameras designed to use a roll of film which is pre-exposed with images such as greeting messages and decorative borders on respective normal exposure frames, are known. Conventionally, the pre-exposure of such images is carried out by actually taking photographs of hard copies of the images on the relevant parts of the respective frames, with the remaining parts of the frames unexposed for subsequent normal photograph taking. This pre-exposure method is found to be not only time consuming but also inflexible in terms of the combination and/or order of the images to be pre-exposed on the film rolls.
The invention seeks to mitigate and/or at least alleviate such problems by providing a new apparatus for and a new method of pre-exposing camera film with images.
According to the invention, there is provided an apparatus for pre-exposing a length of photographic film with a series of latent images for subsequent use in a camera, comprising a control unit having a storage device for storing said images, image generating means for producing an optical image from said storage device, film housing means for housing a length of film between a film supply means and film take-up means, film advance means for advancing the film between the film supply and take-up means, and a lens for, in use, focusing the image onto the photographic film.
In one embodiment, the image generating means is a cathode ray tube controlled by the control unit to produce a scanning light beam. A color filter may be provided between the cathode ray tube and the lens for changing the color of the light beam. More preferably, the filter is provided by a filter wheel which incorporates a plurality of filters of different colors for selective use. It is preferred that the filter wheel is automatically rotatable under the control of the control unit.
In this embodiment, a first support is provided for supporting a film supply means holding a roll of the film, a second support is provided for supporting a film take-up means to receive the film fed from the film supply means, and the cathode ray tube and the lens are provided at an intermediate position between the two supports for pre-exposing the film in transit. It is preferred that the apparatus includes another support which is provided at the same intermediate position for supporting the film in transit for pre-exposure.
It is preferred that the apparatus includes an enclosure providing a light-tight environment for housing the cathode ray tube and the lens as well as the film supply and take-up means. More preferably, the enclosure has a central chamber for housing the cathode ray tube and the lens and opposite side chambers for housing the respective film supply and take-up means.
Advantageously, the apparatus is adapted to pre-expose a bulk roll of film for subsequently cutting into a plurality of shorter film roll strips for individual use in a camera.
The apparatus may include a sensor arranged to detect a pre-punched hole of the film for determining the position of the film.
The image generating means may alternatively comprise the display screen of a computer terminal, which include a cathode ray tube or may be liquid crystal display screen. In this embodiment the film may be housed in a photo-taking device having an exposure opening closed by a shutter means. A light-tight hood may here be arranged between the screen and photo-taking device.
In a further aspect the invention resides in a method of pre-exposing with a series of latent images a length of photographic film for subsequent use with in a camera in an apparatus which has a control unit having a storage device in which an image or a plurality of images are stored and an image generating means to produce an optical image from said storage device, the method involving retrieving a first stored image and generating this on said image generating means, and focusing with a lens said optical image onto a portion of said photographic film for a predetermined period, retrieving a second stored image and generating this on said image generating means, and focusing with a lens said second optical image onto a different portion of said photographic film.
Preferably, the method further comprises the steps of sequentially retrieving a plurality of stored images, generating these on the image generating means and focusing these sequentially onto the length of photographic film. The second and subsequent images may be different or the same as the said first image.
The method may include using an image generator in the form of a cathode ray tube to produce a scanning light beam which is focused on the film in which case a color filter may be used between the cathode ray tube and the lens for changing the color of the light beam. The method may include the step of providing a first support for supporting a film supply means holding a roll of the film, providing a second support for supporting a film take-up means to receive the film fed from the film supply means, and placing the cathode ray tube and the lens at an intermediate position between the two supports for pre-exposing the film in transit. More preferably, the method includes the step of providing another support at the same intermediate position for supporting the film in transit for pre-exposure.
In a preferred embodiment, the method is adapted to pre-expose a bulk roll of film, and includes the step of subsequently cutting the pre-exposed film into a plurality of shorter film roll strips for individual use in a camera.